Dealing with Sickle Cell Disease 0

Hemoglobin, (Hb) is the oxygen-carrier protein found in Red Blood Cells. Hemoglobin consists of four helical polypeptide chains (two alpha chains and two beta chains) and four heme groups.

Biochemistry

Each of the four chains, folds around and shelters a porphyrin ring that has an iron atom at its center. Oxygen binds to the iron. The porphyrins rings and their irons are known as heme groups, and they are responsible for the red color of blood.

The alpha chains are identical and have 141 amino acids each, the beta chains are identical and have 146 amino acids each.

It is the replacement of the amino acids, at position 6 on the beta chains that leads to abnormal hemoglobin and sickle cell diseases.

Glutamic acid is the amino acid that normally occupies the 6th position on the beta amino acids chains. Normal hemoglobin A (Hb-A), has glutamic acid occupying the 6th position on the beta chains.

In Hb-S, valine is the amino acid found at position 6 on the beta chain of amino acids.

In Hb-C, lysine is the amino acid found at position 6 on the beta chains of amino acids.  

In the absence of oxygen, and in acidic environment, the Hb-S chains join together to form long chains that distort the shape of their RBC membranes, leading to the formation of rigid, sickled shape (banana-shaped) RBCs.

The sickling of RBCs leads to two major problems.

1) The sickled RBCs become rigid and sticky. As they travel through small blood vessels, they get stuck and clog the blood flow.  

Clogging may cut-off the blood supply to various tissues and organs in the body causing pain infections and even strokes.

2) The sickled RBCs have a shortened lifespan. They are prone to being swallowed by macrophages (special type of WBCs) and/or getting destroyed by the Spleen. This leads to persistent hemolytic anemia.

The lifespan of normal RBCs is about 115 days. The lifespan of Hb-S RBCs is 10-20 days.

GENETICS

About 1.9% of newborn babies in Ghana carry two sickle cell genes (“S”) one from each parent. Homozygous Hb-SS, is the severest form of sickle cell disease

About 30 % of Ghanaians have the sickle trait, they carry one “Hb-S” gene and one normal “Hb-A” gene. They are said to be heterozygous. Hb AS.

The Hb-S gene may be inherited from either parent in an autosomal recessive pattern

If both parents carry the sickle trait, that is, if both parents have Hb-AS genes, then with each and any of their pregnancies, the child born to them, shall have  

. 25% chance of inheriting 2 “Hb-S” genes, the Hb-SS, one from each parent (full-blown sickle cell anemia)

. 25% chance of inheriting two normal genes, the Hb-AA (normal)

. 50% chance of inheriting one “S” and one Normal “A” gene, the trait: Hb-AS (sickle trait)

In those with sickle traits, about 40% of their hemoglobin is Hb-S and 60%, Hb-A.  



SICKLE CELL TRAIT AND MALARIA PARASITE (Plasmodium falciparum)

Plasmodium falciparum causes acute and severe malaria infections. It can enter all RBCs.

However, when Plasmodium falciparum, the malaria parasite enters Hb-S type of RBCs, it triggers sickling in those RBCs.  

The sickled cells are either rapidly swallowed by macrophages or destroyed by the spleen. The term suicidal infection has been used to describe this phenomenon.

This suicidal infection helps children with the sickle trait, (Hb-AS), and who are less than 5 years of age, to eliminate the malaria parasite from their bodies, and to withstand severe malaria infections until they develop full resistance to severe malarial infection, later on.  

So young children, under 5 years with the sickle trait, (Hb-AS) have the advantage in fighting off severe malaria infections, compared to their cohort who are either Hb-AA or Hgb-SS.  

Actually, those with Hb-SS perform poorly and are highly susceptible to the lethal effects of malaria infections.

It is estimated Hb-AS provides 60% protection against Malaria Deaths in children 2-16 months old (1)



MANIFESTATIONS AND COMPLICATIONS OF SICKLE CELL DISEASES

Symptoms of sickle cell diseases, are delayed until the child is 6-12 months old. Newborn babies and infants do have high levels of fetal hemoglobin, Hb-F, in the circulation. Hb-F, retards sickling formation.

Swelling of the hands and feet in an infant is the first symptom of Hb-SS. It is due to sickled RBCs blocking blood flow in and out of the hands and feet.  

This condition is treated with fluids and pain medicines.

The markers of sickle cell diseases are:

 – Hemolytic Anemia (RBCs destruction leading to anemia)

– Painful occlusion of blood vessels

 – As a result of frequent cut in blood supply, there are multiple microscopic areas of tissue death, microinfarcts, in many organs, including the Brain, Spleen and Kidneys.  

Sickle cell complications can occur in any organ system and lead to severe decrease life expectancy.



(I) PAINFUL EPISODES

Painful episodes are characteristics of Sickle cell diseases. Pain may be acute or chronic.

Pain results from cut of blood supply to the affected areas.

PRECIPITATING FACTORS:

– Sudden change from Warm to Cold Weather (leading to vasoconstrictions)

– Dehydration (from exertion or working out in the sun, when the weather is hot)

– Infections

– Alcohol intoxications

– Physical and Emotional stress

– Comorbidity: Pregnancy, Asthma, Sleep apnea, Acidosis

Acute pain requires: Narcotic analgesics, rehydration, warmth, NSAIDs and adequate rest  



AVOIDANCE OF PAINFUL EPISODES:

 Drink plenty of fluids

 Try not to get too hot or too cold.

 Avoid high altitudes, and places with low oxygen levels



Acute Hepatic Crisis

Due to vaso-occlusive sickling episodes in the liver, a person may develop sudden liver enlargement, elevated liver enzymes, and pain in the liver area.   

The right upper quadrant abdominal pain does not last long, but this condition must be distinguished from the associated Liver sequestration crisis.

Sequestration Crisis

Sequestration occurs when large number of sickle cells get trapped in the Spleen or Liver, causing these organs to enlarge. Sequestration is characterized by the following:  

Signs: Liver and or splenic enlargement (Splenic sequestration) and. Rapid fall in Hemoglobin levels

Symptoms: sudden weakness, pallor, fast breathing, fast heartbeats, extreme thirst and abdominal pain.

Sequestration crisis is treated with Blood transfusion and Exchange transfusions to improve the anemia

Acute Chest Syndrome (ACS)

This condition is due to vaso-occlusion in the lung circulation. The Hb-SS person develops sudden  

 – Chest pain. Fever with temperature> 101.3F. Fast breathing. Wheezing. Cough

 – Chest X-ray shows infiltrate in one or more lung segments.

ACS is treated in the Intensive care, with Oxygen, taking deep breaths, Antibiotics and Exchange blood transfusions

(ii) HEMOLYSIS

Sickle cell disease is associated with RBC destruction and perpetual anemia. Most sickle cell RBCs, survive only 10-20 days.

The end products of hemolyzed RBCs: free Hemoglobin and Arginase, are toxic to the inner linings of small blood vessels, they lead to destruction and narrowing of blood vessels. Arginase degrades Arginine, the substance required to form Nitric oxide. Nitric oxide opens up small blood vessels, and in its absence, the vessels collapse, and free radicals pile up.  

Hgb-SS persons are prone to develop Pulmonary Hypertension, due to free plasma Arginase.

The short lifespan of sickle RBCs, cause the bone marrow to overwork, to produce more RBCs. There is bone marrow hyperplasia in all the skeletons.

(Iii) MICROINFARCT

Spleen

Recurrent microinfarct in the Spleen, due to frequent cuts in blood supply, destroys the spleen’s ability to fight infections. Hb-SS persons are susceptible to Pneumococcus, H. influenzae, Salmonella, Mycoplasma and E. coli infections

Brain

Sickle cell disease Children are at risk for Ischemic stroke during their childhood, and as they advance in age.

About a third of sickle cell disease persons have silent brain infarcts.

In children (2-16 years) Annual intracranial doppler Ultrasound of the Middle Cerebral Artery, is done to assess the flow velocity and predict the risk of a stroke.

Transfusions to decrease Hb-S level<30% prevents stroke in children with high Cerebral Blood Flow(>200cm/s) Hydroxyurea therapy, does not prevent strokes.

In general, the lower the baseline hemoglobin level in Hgb-SS persons, the higher the decline in their cognitive functions (memory, processing speed and executive functions)

Kidney

Decrease blood flow to the medulla, and infarct in the renal papilla, eventually lead to Chronic Kidney Diseases. Hgb-SS persons may have protein and blood in their urine, and marked decrease in filtration rate. The kidney can no longer concentrate urine, excrete potassium and acids. To prevent further kidney destruction, Blood Pressure control is a must, target <130/80 mmHg.



OTHER COMPLICATIONS

Priapism

About 35% of men with sickle cell disease, have prolonged and painful erections. It is related to obstruction of venous drainage of the penis.  

Treatment include: aspiration of blood from the cavernous veins of the penis, and irrigating them with dilute epinephrine solution

Priapism may lead to penile fibrosis and impotence.

Foot and Leg ulcers

Leg ulcers are usually seen in 10-50 years old with sickle cell disease.

Impaired circulation leads to traumatic and sometimes spontaneous leg ulcers at the medial and lateral ankles.  

Wound debridement, and bandaging with Zinc oxide impregnated bandages help.

Aplastic Crisis 

This usually occurs with Parvo b19 infections which attack the RBC precursors in the bone marrow. Folic acid deficiency and ingestion of toxins like phenylbutazone, may precipitate aplastic crisis.  
Aplastic crisis is managed with blood transfusion and supportive care.



GENERAL MEASURES IN MANAGEMENT OF SICKLE CELL DISEASES

Hgb-SS persons should avoid: Alcohol, Cigarette, marijuana, Cocaine, as well as non-prescription medications.

CHILDREN

Screening for sickle disease done at birth, followed by Hb-electrophoresis.

Penicillin prophylaxis (up to age 5 years) prevents sepsis due to streptococcal pneumonia in children

Prevnar (Pneumococcal vaccine) prevents pneumococcal infection in children

Transfusions to reduce Hb-S levels <30% prevents stroke in children with high cerebral blood flow

HYDROXYURIA. This medication

– increases total Hb-F in sickle cell disease. Hb-F retards gelation and sickling of RBCs

– Effective in Reducing painful episodes,  

– Helpful in reducing number of Acute Chest syndromes and Sickle cell crises.



BONE MARROW TRANSPLANT

This can CURE sickle cell disease. Not widely used.

By: Dr Sarkodie

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What Is It Rheumatoid Arthritis( RA) and How to Diagnose It Correctly 0

Rheumatoid arthritis (R.A.) is a chronic inflammatory disease. Although it mainly affects the joints, it can also affect a large number of organs and even some tissues.  It’s an auto-immune reaction which causes inflammation in the affected areas in a degenerative, chronic manner.

Although the course of this disease varies from individual to individual, it’s often characterised by active stages or ‘flare-ups’ and passive stages or ‘remissions’; it is during the passive stages or remissions that the individual is free of symptoms and, if unaware of how R.A. ‘works’, he or she may wrongly believe that the disease has disappeared.

Moreover, some passive stages are very deceptive: for example, you may have a mild temperature for very long periods and suffer from mild anaemia, perhaps feeling a little tired though not necessarily. This is a common subtle stage of R.A in which many affected people are completely unaware; if they go to the doctor he or she may completely overlook the possibility of R.A. and allow this degenerative disease to continue its hidden ‘onslaught’.

If left completely untreated the affected individuals may, in the later stages, develop joint destruction with some deformity and severe mobility impairments, together with chronic pain and potential damage to other organs.

It is therefore advisable that you are very aware of your body, that you learn all you need to know about R.A. so that you can quickly determine if it’s worth asking your doctor for the necessary tests, some of which very easy and affordable. I will list these tests further down.

The symptoms of R.A in its active stages (flare-ups) are:

  • joint pain, joint stiffness and, at times, joint redness and swelling
  • the range of motion in the affected area/s is diminished
  • Muscular pain, mild fever and (sometimes) anaemia (lower red cells count in your blood)
  • Initially only hands (one or both, especially the fingers) may be affected, sometimes only the feet. Then the elbows or ankles may be affected. Then one or both knees. This may be a dull chronic pain or only some unspecified stiffness with particular sensitivity to cold water and cold weather. Later on the pain may increase and become more chronic.

In the later stages R.A. may cause

  • Skin redness or skin inflammation
  • Round nodules under the skin (which are painless)
  • Swollen glands
  • Deformities of hands and feet (this is one of the later stages of R.A.)

How to properly diagnose R.A. to avoid making the mistake of ignoring it:

1 – If you think some specific joint areas may be affected, even if only your hands, an easy way to diagnose whether you suffer from R.A. or not is through a simple X-Ray of the affected area. This is how I was diagnosed with R.A. at only 14 years of age, by pure chance whilst I was being treated for a finger injury. I was completely unaware I was suffering from it and until then my doctors had completely overlooked my chronic mild fever and my chronic mild anaemia.

2 – Through a blood tests, you can ask your doctor to check your ESR (Erythocyte Sedimentation Rate), your CRP (C-Reactive proteins) and possibly an overall CBC (complete blood count)

Banana Facts and Information 0

This article is a brief study on Bananas, the history of the Banana Plant and tips on growing Banana Plant.

Banana Facts

Banana “Trees” are not actually trees but are herbaceous plants in the genus Musa and of the family Musaceae. Due to their size, shape and structure, they are often mistaken for trees. Bananas are largely cultivated for their fruit. But the plant is also used as ornamental plants in gardens.

Typically, there are two types of Bananas that are cultivated, mainly in tropical regions. Firstly, there is the sweet dessert fruit that is eaten raw or used in dessert recipes. There are a wide variety of delicious dessert recipes using Bananas in almost every food culture in the world.

Secondly, plantains are from a group of cultivars with firmer fruit and used generally in cooking vegetable-based dishes like curries. Plantains are especially popular in South-East Asia, India and Jamaica.

History of Bananas

Banana plants were first cultivated for domestic use in Southeast Asia. There is evidence found in Papua New Guinea that shows banana cultivation there dates back to, possibly, 8000 BC. This would mean the Western Highlands of Papua New Guinea was probably the first place were Bananas were cultivated. A whole lot of wild Bananas still grow in Papua New Guinea, Malaysia, Indonesia and the Philippines.

The first time Bananas were talked about in written history was in Buddhist texts around 600 BC. Then, the famous explorer, Alexander the Great found the fruit in India in 327 BC. The very first plantations were said to exist in China way back in 200 AD.

The History of Bananas continued with Islamic Conquerors bringing the fruit to the Middle East and later on, Arab Merchants exposed most of Africa to Bananas. Interestingly, the word Banana is actually of West African origin.

After that, banana cultivation exploded in most of the rest of the world thanks largely to Portuguese colonists who started banana plantations in the Atlantic Islands, Brazil and western Africa. Unfortunately for the Europeans, Bananas were not heard of in Europe until the Victorian Era and even then, only through merchant trade.

These days, Bananas can be found in practically every market in the world without much trouble at all and hurrah for everyone!

Tip and Techniques-Growing Bananas

Growing Banana Plants are easy enough if the right combination of factors is present. A Banana Plant takes about nine months to become mature and it needs a lot of tender loving care for it to grow to its fullest potential.

Generally, a Banana Plant lives up to approximately 25 years. Bananas grow from stems that grow from the ground up called rhizomes and it produces suckers that grow from the main stem of the Banana Plant. Rhizomes have a lifespan of 15 years or more.

The upright plant is called a pseudostem and when it matures, will reach an average height of 2 – 8 metres and the leaves grow up to 3.5 metres in length. Interestingly, each pseudostem produces only a single bunch of bananas. It then dies and is replaced by a new pseudostem.

Growing Banana Plants require a lot of sunlight and a high level of humidity. That is one of the reasons it’s found in abundance in the tropics and hot climate countries. While it is growing, it requires watering every day and a balanced fertilizer to ensure it grows well. The right temperature for growing Banana Plant should be in approximately 80 degrees Fahrenheit during the day.

The soil has to be nutrient-rich and slightly acidic. It should also be able to retain moisture but not much, like roots that are filled with water, will die very fast. When all the right ingredients are present, the Banana Plant grows very quickly and it is a pleasure watching it grow. Not only does it bear fruits, but it is also a beautiful ornamental plant and really stands out in any garden.

 

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